<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
</head>

<body>
  <div id="app"></div>
  <script type="text/babel">

    /* class App extends React.Component{
      constructor(){
        super();
        //构造器中的this指向组件实例
        this.handle = this.handle.bind(this)
      }

      state = {
        count:0
      }

      render(){
        const {count} = this.state;
        return (
          <div>
            <button onClick={this.handle} >+</button>
            <p>{count}</p>
          </div>
        )
      }

      //事件函数
      handle(){
        alert(1)
        //在组件中,我们希望事件函数的this指向组件实例,这样可以拿到state等各种数据
        console.log(this);
      }
    }

    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>) */

    

    class App extends React.Component{
      constructor(){
        super()
        this.handel = this.handel.bind(this);
      }

      state = {
        count: 666
      }

      render(){
        const {count} = this.state;
        return (
          <div>
            <button onClick = {this.handel}>+</button>
            <p>{count}</p>
          </div>
        )
      }

      //事件函数
      handel(){
        alert(1)
        //在组件中,我们希望事件函数的this指向组件实例,这样可以拿到state等各种数据
        console.log(this);
      }

    }


    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>)


  </script>
</body>

</html>